ATI Radeon HD 5770 – DirectX 11 for the Masses

AMD may have released its first Evergreen GPUs mere weeks ago, but don’t think it’s slowing down for anybody. The company has followed-up with its first mid-range parts, belonging to the HD 5700 series. Performance is much more modest on these new cards, but no features have been scrapped. It’s all here… DirectX 11, Eyefinity and more.

Closer Look at ATI’s Radeon HD 5700 Series

It’s time to get into what this article’s all about… our look at ATI’s Radeon HD 5770. This is of course the company’s brand-new mid-range graphics card, and it will carry an SRP of $159, putting it right below NVIDIA’s GTX 260 in terms of retail value. Over the past few months, there have been many rumors that the HD 5770 would be comparable in performance to the HD 4870, and for the most part, that’s true. Both cards share a similar number of steam processors, but both also trade various other pros and cons, with the overall nod going towards the HD 4870.

The easiest way to look at the HD 5770 is to consider it as being half of an HD 5870, because in most regards, that’s exactly the case. The block diagram for the HD 5770 is seen above, and as you can see, it is indeed almost like the HD 5870’s, but cut in half. There are some minor detail changes, and the end result is that the HD 5870 has slightly more than double the number of transistors, but nothing is lacking from the HD 5770 from a features standpoint… only performance.

To help prove this “half” metric, take a look at the table below. Rather than comparing all four of the current HD 5000-series cards, I’d opted to single out the HD 5870 and HD 5770, as they’re both the “top card” in their respective category (mid-range vs. high-end). As you can see, the HD 5870 pretty much doubles everything, from the number of stream processors to the number of texture units and ROPs. Of course, the various performance measurements are doubled as well. The exception is the GDDR5 data rate, which remains the same as both cards feature 1GB of GDDR5, and at the same memory clock of 1200MHz. The GPU core clock is also the same on both cards, at 850MHz.

Specification

Radeon HD 5770

Radeon HD 5870

Process

40nm

40nm

Transistors

1.04B

2.15B

Engine Clock

850 MHz

850 MHz

Stream Processors

800

1600

Compute Performance

1.36 TFLOPS

2.72 TFLOPS

Texture Units

40

80

Texture Fillrate

34.0 GTexel/s

68.0 GTexel/s

ROPs

16

32

Pixel Fillrate

13.6 GPixel/s

27.2 GPixel/s

Z/Stencil

54.4 GSamples/s

108.8 GSamples/s

Memory Type

GDDR5

GDDR5

Memory Clock

1200 MHz

1200 MHz

Memory Data Rate

4.8 Gbps

4.8 Gbps

Memory Bus

128-bit

256-bit

Memory Bandwidth

76.8 GB/s

153.6 GB/s

Maximum Board Power

108W

188W

Idle Board Power

18W

27W

There’s one “loss” suffered by the HD 5770 that’s worth noting, though… the power consumption. The given TDP of the HD 5770 isn’t exactly half, nor would we expect it to be, but it’s impressive nonetheless… just 18W idle. Finally, we’re seeing GPU companies taking power consumption seriously. Even if you’re the furthest thing from an enviro-nut, I’m confident most would agree that a GPU idling at 18W is far better than one that idling at 80W.

I can’t stress how important these gains (or rather, losses) are, because just imagine how much power is consumed by the idle GPUs the world over, compared to what it could be like with GPUs such as these. The differences are huge. To put it in perspective, the HD 4870, which offers similar performance as the HD 5770, idles at 80W. ATI has effectively decreased idle power consumption by 77.5% in just one generation.

Wow.

Below is AMD’s current GPU line-up, including the HD 5750, also released today. You’ll notice an absolute lack of X2 cards, and that’s not an accident. In looking around the web, it’s become clear that those have been phased out, and it’s no surprise, as the HD 5870 X2 (Hemlock) is due very, very soon. Earlier, I equated the HD 5770 to being one-half of an HD 5870, and the same could almost be said when comparing the HD 5750 to the HD 5850. The primary difference is that the HD 5770 has a slower GPU clock (-25MHz), but faster memory clock (+150MHz).

AMD claims immediate availability of both of today’s launches, but I’d personally expect the HD 5770 to be much easier to acquire over the course of the next few weeks based on what I’m hearing from some vendors. We didn’t receive an HD 5750 in time for this article, but you can expect our look at it in the weeks to come.

Model

Core MHz

Mem MHz

Memory

Bus Width

Processors

Radeon HD 5870

850

1200

1024MB

256-bit

1600

Radeon HD 5850

725

1000

1024MB

256-bit

1440

Radeon HD 5770

850

1200

1024MB

128-bit

800

Radeon HD 5750

700

1150

512 – 1024MB

128-bit

720

Radeon HD 4890

850 – 900

975

1024MB

256-bit

800

Radeon HD 4870

750

900

512 – 2048MB

256-bit

800

Radeon HD 4850

625

993

512 – 1024MB

256-bit

800

Radeon HD 4770

750

800

512MB

128-bit

640

Radeon HD 4670

750

900 – 1100

512 – 1024MB

128-bit

320

Radeon HD 4650

600

400 – 500

512 – 1024MB

128-bit

320

The HD 5770 features a near-identical shroud as the already-released HD 5870 and HD 5850, and while it does a sufficient job of keeping the GPU cool, I can’t help but think of it as looking like a toy. Who can blame me? It’s a good thing the performance proves it’s the furthest thing from one.

While the HD 5870 and HD 5850 cards have two PCI-E power connectors, both the HD 5770 and HD 5750 have just one, situated inside of the top portion of the card’s chassis. Note that the similar-performing HD 4870 of last summer required two power connectors, so the power consumption differences are noticeable from a physical standpoint as well.

Just because the HD 5700 series are AMD’s mid-range cards, it doesn’t mean that the company cheapened out and removed Eyefinity support. It’s actually the opposite, with two DVI ports ready to go, along with both HDMI and DisplayPort connections as well. What’s most exciting about the company’s inclusion of this, to me, is with the HD 5750. That card is to sell for $110, and gaming performance aside, that’s one heck of a deal for a card that’s able to power 3x 2560×1600 displays. For all we know, it might be financial gurus that are picking these cards up in droves, as they typically have robust multi-monitor setups.

Before we dive into our testing results, I’ll reiterate that given the specs, we can expect the HD 5770 to fare quite nicely when compared to the HD 4870 (which retailed for $400 at its launch last summer). It’s hard to say that the HD 5770 is only a lesser-expensive HD 4870, though, because the older card lacks DirectX 11 support, has a far higher power consumption, greater temperatures, lacks Eyefinity support, nor does it offer Dolby True HD via HDMI. Overall, the HD 5770 is a win/win any way you look at it.

On the following page, we’ll tackle our system specifications and testing methods, and then we’ll kick off our results with Call of Duty: World of War.